I think the algo of like and share is back when a post get lots of engagement it is showed to the fans who like your page again and again thats what i observe. so reach become high for multiple times a post showed to fans later fans engage.

Note that adblockers might block our captcha, and other functionality on BHW so if you don't see the captcha or see reduced functionality please disable adblockers to ensure full functionality, note we only allow relevant management verified ads on BHW.